Water Supply Outlook for Alberta

December 2008

November 2008 Precipitation

Above to much above normal precipitation was recorded in most of the northern half of Alberta, except the Fort Chipewyan area which recorded below to much below normal precipitation. Generally, much below normal precipitation was recorded in the southern half of the province, except precipitation was below normal to normal in a narrow area between Sundre and Lethbridge and in some mountain areas west of Banff and south of Jasper. Precipitation was much above normal in the Cypress Hills area (Figure 1). November precipitation totals are illustrated in Figure 2.
 

Fall Precipitation (September 1 to October 31, 2008)

Much below normal precipitation was recorded in central areas of Alberta, from Medicine Hat through Calgary to Cold Lake and Grande Prairie. Generally above to much above normal precipitation was recorded in Lethbridge, Cypress Hills and Milk River in southeastern Alberta and at High Level in northeastern Alberta. Northern Alberta recorded generally below normal to normal precipitation, as did mountain and foothill areas west of Calgary and High River. Most other mountain and foothill areas recorded below to much below normal precipitation (Figure 3). Fall precipitation totals are illustrated in Figure 4.

Alberta Agriculture models soil moisture for non-mountainous, agricultural areas of Alberta. Soil moisture at the end of October 2008 is illustrated in Figure 5, which shows almost all of southeastern and part of west central region are nearly wet and most of the agricultural areas in northwestern and north central Alberta are dry.

 

Long-Lead Precipitation Outlook

Environment Canada's long-lead Deterministic forecast for Alberta issued on December 1, 2008 for the December 2008 through February 2009 period is for above normal precipitation in Alberta. Below normal temperatures are forecast for the northern one-third of Alberta and normal temperatures are forecast for the remaining southern two-thirds of Alberta. Environment Canada's long-lead precipitation outlook, along with an assessment of the forecast method's historica accuracy, is available from their website located at: http://weatheroffice.ec.gc.ca/saisons/index_e.html.

The National Oceanic and Atmospheric Administration (NOAA) long-lead forecasts issued on November 20, 2008 for December 2008 through to the end of February 2009 is for an even chance of below normal, normal or above normal precipitation and temperatures in southern Alberta. The NOAA reported on December 8, 2008 that ENSO-neutral conditions (no El Nino or La Nina) are likely to continue into early 2009. NOAA's long-lead precipitation outlook is available from their website located at: http://www.cpc.ncep.noaa.gov/products/predictions/90day/.

Note that forecasting for such a long time period into the future is very difficult, and so ths historical accuracy has been variable, depedent on location and time period, and is often low, more so for precipitation than temperature.


For technical enquires about this web page please contact Alberta Environment - Environmental Management Water Management Operations Branch at AENV-WebWS@gov.ab.ca